SRD:Manual of Gainful Exercise

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Manual of Gainful Exercise: This thick tome contains exercise descriptions and diet suggestions, but entwined within the words is a powerful magical effect. If anyone reads this book, which takes a total of 48 hours over a minimum of six days, she gains an inherent bonus of from +1 to +5 (depending on the type of manual) to her Strength score. Once the book is read, the magic disappears from the pages and it becomes a normal book.